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VanArnam Vineyards - The life of a wine grape
Harvest 101 - Life in the Vineyard

Harvest 101 – Learn what goes on behind the scenes all year in the vineyard leading up to the annual harvest of the grapes.

For winegrowers, the big event the whole year’s efforts lead up to is Harvest.

Metamorphosis – Veraison

Grape ripening begins with the growth period known as veraison, when the grapes on the vines transform from small, green, hard berries into a lush ripened fruit.  Vines enter this stage of ripening between 30-70 days depending on the variety and climate; after the fertilized flowers have fallen off and become grape clusters.  This typically happens in July or August in the Northern Hemisphere and January or February in the Southern.

During veraison, the grapes lose their green color and take on darker hues – greenish yellow for white varieties to red, purple or almost black for red varieties.  The grapes soften and increase in size as the vine begins to pump sugar into the grape; while acidity starts to decrease. 

Veraison doesn’t happen at he same time throughout the vineyard.  Grapes exposed to more sun and warmth get a head start to those in shadier, cooler areas.

Crop Size and Protection

Controlling the crop size is important to top grape growers.  They believe that if the vine has fewer bunches the grapes will ripen more fully and be of higher quality. 

Caring for the crops is a full time job in itself.  Grape growers not only have the weather to contend with but also the threat of various organisms such as insects, mildew, rot, other fungi, bacteria and viruses that can damage the grapes or even kill the vines.

So how do winegrowers know when to pick the grapes?

Depending on the variety and region, the ripening process can last anywhere from 30-70 days after veraison.  Some grapes like our award winning Tempranillo – the name comes from the Spanish term for “early” – ripen very quickly.  Others such as Petit Verdot, ripen much later.  Regions like Germany with its cooler climate typically have a longer ripening cycle compared to hotter climates such a Washington or California’s Central Valley which have a shorter one.

During this period, the growers closely monitor the development of the grapes.  As the grapes ripen they become sweeter and the acidity levels decrease and the sugars, which will be fermented into alcohol, increase.  As the skin color of the grape intensifies in darkness the flavor components found in the skins, stems and seeds that contribute to the texture soften.

Winemakers will test grape juice from across different parts of the vineyard to check for pH and Brix (measurement of sugar) to help them determine how ripe the grapes are.  The exciting part of winegrowing is wandering through the vineyards regularly to taste and examine the grapes in the weeks leading up to harvest.

They are checking for what’s referred to as physiological ripeness – gauging the intensity of flavors and the quality of the tannins.  Ultimately they are seeking a good balance of acidity, sugars, tannins and flavor compounds.

As harvest nears, it is important to monitor the weather reports closely and stay ahead of any sudden changes.  Heat waves, too much rain and even frost can ruin a crop.

The date of harvest is never the same from year to year for various reasons such as weather variations or the style of wine being made.

Harvest Time

At last, it’s harvest time.  When the winemaker decides the time is right, it’s all hands on deck.  All of VanArnams grapes are harvested by hand; with vineyard workers using shears and a bin.  Our trained workers can identify properly ripened grape bunches. Once the best grapes have been selected and destemmed, it’s time to crush them so the yeast can start getting to work fermenting.

The winemakers job does not stop here, but that’s another post.  Stay tuned!


 Noelle Cook

Post By:   Noelle Cook